Carbon-14

The graph below represents the decay of a radioactive isotope into a stable disintegration product. Which remains could be dated using this radioactive isotope?

• A) seeds from the earliest grasses

• B) mastodon bone

• C) feathers from the earliest birds

• D) Naples tree trunk

Tags

NGSS.HS-PS1-8

The graph titled "Decay of a Radioactive Isotope" shows the rate of decay of a radioactive isotope through two half-lives. Each box in the diagram represents the ratio of atoms of the radioactive isotope to atoms of the disintegration product at different half-lives. The box at two half-lives has been left blank. Which box best represents the ratio of these atoms at two half-lives?

• Box A

• Box B

• Box C

• Box D

Tags

NGSS.HS-PS1-8

What percent of carbon-14 would be left after 5730 years?

• 100%

• 75%

• 50%

• 25%

Tags

NGSS.HS-PS1-8

What percent of carbon-14 would be left after 11,460 years?

• 100%

• 75%

• 50%

• 25%

Tags

NGSS.HS-ESS2-6

NGSS.HS-PS1-8

What percent of carbon-14 would be left after 11,460 years? (2 half lives)

• 100%

• 75%

• 50%

• 25%

Tags

NGSS.HS-PS1-8

If one-fourth of the carbon-14 is remaining then how many half-lives have passed?

• 1

• 2

• 3

• 4

Tags

NGSS.HS-PS1-8

A bone was that originally had 10 grams of Carbon 14 now has about 1.25 grams.  How many YEARS have passed? (not half lives)

• 3

• 5730

• 6000

• 17,200

Tags

NGSS.HS-PS1-8

The table shows the radioactive decay of carbon-14. Part of the table has been left blank.
After 22,800 years, approximately what percentage of the original carbon-14 remains?

• 15%

• 12.5%

• 6.25%

• 3.125%

Tags

NGSS.HS-PS1-8

All organisms contain the element_________, so it is used to find the ages of fossils.

• carbon-14

• carbon-12

• carbon

• carbon age

Archeologists have found a fossil that contains 87.5 grams of nitrogen-14 and 12.5 grams of carbon-14. The half life of carbon-14 is 5730 years. How old is the fossil?

• 3 million years

• 17,190 years

• 11,460 years

• 92,000 years